Strand tensioning device



R. PAULSON STRAND TENSIONING DEVICE Nov. 18, 1969 Filed July 18, 1967 2 Sheets-Sheet 1 INVENTOR RAYMOND PAULSON Jed/Lg @241; L W

ATTORNEYS Nov. 18, 1969 Filed July 18. 1967 R. PAULSON 3,478,982

STRAND TENSIONING DEVICE 2 Sheets-Sheet 2 ATTORNEYS United States Patent 3,478,982 STRAND TENSIONING DEVICE Raymond Paulson, Fremont, Ohio, assignor to Samuel lllgore and Company, Mantua, Ohio, a corporation of Filed July 18, 1967, Ser. No. 654,163 Int. Cl. B65h 59/18 US. Cl. 242-129.8 12 Claims ABSTRACT OF THE DISCLOSURE A device for controlling the tension of a fibrous strand as it travels from a spool to a machine. The device comprises a rotatable reactionary member in the form of a capstan around which the strand is wrapped after it leaves the spool. Control is effected by varying the resistance of the reactionary member to rotation. A stationary guide member or capstan having a spiral peripheral groove merges with an annular groove in the rotating capstan whereby the strand can move smoothly from one groove to the other. An adjustably mounted guide bar controls the direction of the movement of the strand as it passes from the reactionary member to the machine.

BACKGROUND OF THE INVENTION Field of the invention The invention relates to bobbin and cap winding and particularly to a device for controlling the tension upon a strand as it passes from the supply spool to a machine.

Description of the prior art Heretofore in the manufacture of high pressure hose the practice has been to employ a braiding machine for braiding a layer of fibrous reinforcing material around a core of elastomeric material. The strands were mounted upon rotating spools which in turn were mounted at spaced intervals around a rotating support. Difficulty has been experienced in maintaining uniformity of tension on the strands because of the necessity for braking the total rotating mass which varied as the size of the bobbin was reduced as the strand was withdrawn from the bobbin. Such change in mass also required a change in the tension and thus required an objectionable loss of time to maintain a desired uniformity of tension at the point of application of the strand to the tube.

The problem has been solved by the present invention by mounting the bobbin upon a relatively stationary support and controlling the tension on the strand as it moves from the bobbin to the point of application on the tube. In such operation, the braiding machine pulls the strand from the bobbin. The relatively stationary bobbin allows the use of a solid one-piece spindle which eliminates the bearing binding problem incident to the use of a rotating spindle and enables the strength of the spindle to be increased, thus allowing a larger bobbin to be used and enabling a higher lapping speed to be attained by the braiding machine.

Removing a strand from a relatively stationary bobbin requires so little force that the strand has a tendency to form loops, due to centrifugal force, but the present invention has solved that problem by utilizing a guard in the form of a canister around the bobbin and by devising a device which is carried by the canister for controlling the tension on the strand in accordance with the requirement of the winding machine.

SUMMARY OF THE INVENTION The present invention utilizes a relatively stationary "ice bobbin which is supported on a spindle that extends through the bobbin and is supported at one end of a container, or canister. The other end of the canister has a plate with an aperture therein through which the yarn or strand may be passed and also has a tension device which acts as a reactionary member to the pull on the strand exerted by the machine. The tension device comprises a relatively stationary capstan and a relatively movable capstan around Which the strand is wrapped as it is withdrawn from the bobbin. The strand passes first around the relatively stationary capstan and then around the relatively movable capstan, from whence it is passed through a suitable guide member and led to the machine. In the preferred form, the rotatable capstan is mounted upon and is coaxial with the stationary capstan and the mating faces between the two capstans serves as the braking surface.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of part of a container for the bobbin and showing one form of tension device applied thereto;

FIG. 2 is a section taken on a plane indicated by the line 22 in FIG. 1;

FIG. 3 is a vertical section taken through the tension device;

FIG. 4 is a vertical section through a device embodying the present invention but illustrating the support for the bobbin (with the tension device removed); and

FIG. 5 is a partial vertical sectional view of the device shown in FIG. 4 but with a modified form of tension device applied to the strand container.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention embodies a support by means of which a bobbin may be mounted in a relatively stationary position, together with a device for tensioning the strand as it is pulled from the bobbin by the machine which is utilized for winding the strand upon an article to be produced. As applied to a braiding machine, the bobbins are supported upon a plate 10 which is journaled for rotation in a vertical plane and with its axis coincident to the axis of the tube which is being fabricated by the machine. On such machine, the bobbins are supported with their axes parallel to the axis of the supporting plate and at spaced regular intervals thereon. In accordance with the present invention, the bobbin 11 is adapted to be removably positioned upon a spindle 12 which, as shown in FIG. 4, may be attached to the plate 10 by a fastening member 13. The bobbin is positioned within a container 15 which is shown as a cylindrical member having a bottom plate 16 which engages the plate 10 and is adapted to be clamped thereto upon tightening of the nut 13. The upper or outer end of the container 15 is adapted to receive a plate 17 which has a central aperture 18 through which the strand, indicated at 20, may be passed as it is withdrawn from the bobbin.

In the embodiment of FIGS. 1 to 3 the plate 17 is detachably connected to the cylinder 15 in any suitable way. The form shown embodies a quick detachable connection and embodies pins 21 and 22 which may be fixed to the plate and project through openings in the wall of the container 15. The opposite end of the plate 17 may be positioned with respect to the container 15 by means of a spring-pressed latch pin 25 which is slidably mounted upon an elongated recess 26 in the plate for insertion through an opening 27 in the wall of the container. A spring 28 normally urges the pin 25 outwardly while a finger-actuated pin may be used for retracting the pin 25. For such purpose, one end of the pin 30 is fixed to the pin 25 and projects through a slot 31 in the outer end of the plate 17. Thus, upon retraction of the pin 25, the plate 17 may be quickly removed from the container for replacement and rethreading of a new bobbin.

The tension device of the present invention embodies a stationary capstan 35 and a rotatable capstan 36 around which the strand is wrapped at its passes from the container to the machine. In the embodiment of FIGS. 1, 2 and 3, the stationary capstan is fixed to the plate 17 by means of a nut 37 which engages the threaded shank 38 of the stationary capstan. The rotatable capstan in the preferred embodiment is journaled for rotation on another shank 40 of the stationary capstan. Preferably, the rotatable capstan is partially embedded within an annular recess 41 in the stationary capstan. Resistance to rotation may be imparted to the member 36 by adjustment of a nut 45. A ball bearing unit 46 may be interposed between the nut and the rotating capstan 36, whereby tightening of the nut increases the friction between the mating faces of the stationary and rotatable capstans.

By mounting the two capstans in axial alignment the tensioning device has compactness and simplicity in construction. The stationary capstan imparts a coarse degree of friction upon the strand, while adjustment of the nut 45 imparts a relatively fine degree of friction upon the strand. Control is accomplished by providing a helical groove 50 in the stationary capstan and a cylindrical groove 51 in the rotatable capstan, and by so positioning the groove 51 in close proximity to the capstan 35 that the helical groove merges with the cylindrical groove, thus enabling a smooth transition of the strand from one groove to the other. Then by adjusting the degree of pressure exerted against the mating faces of the two capstans a fine degree of control can be obtained.

In the embodiment of FIGS. 1 to 3, the strand is passed around the loop in the guide bar 55 which is adjustably supported on the plate 17, as by a fastening member 56. Additionally, as the strand leaves the rotatable capstan it is guided in its direction of movement toward the machine by a second guide bar 60, which may be adjustably fastened to the plate 17 by a fastener 61. Each guide bar 55 and 56 may be adjusted both angularly and radially with respect to the plate 17 so as to provide a smoothly running strand with the desired degree of tens1on.

In the modification of FIG. 5 the axis of the capstan is coincident with the axis of the aperture 18, wherefore the shank 38 has a passageway extending axially thereof and a radially extending intersecting passageway 66 which provides communication between the passageway 65 and the bottom of the helical groove in the stationary capstan. With such arrangement the strand is threaded through the passageways, then around the stationary capstan and the rotatable capstan, as shown in FIG. 5. In this figure, the parts which correspond to those illustrated in FIGS. 1, 2 and 3 bear the same reference characters but with the suffix a. This modification eliminates the necessity for the guide bar 55.

Either of the foregoing embodiments enables the tension on the strand to be adjusted without requiring the assembly to be dismantled. The utilization of a stationary bobbin eliminates the need for bobbin bearings which are susceptible to binding when in operation.

The tensioning device enables the tension to be held consistently and over a broader range and also enables the tension to be controlled to a much lower value than with previously known systems. A further advantage of the present invention has been the improvement in the quality of the product formed on the braiding machine.

The present invention has been illustrated and described in its preferred embodiments but it is to be understood that changes may be made by those skilled in the art without departing from the scope of the appended claims.

I claim:

1. A device for maintaining tension on a strand as it is withdrawn from a bobbin by a machine comprising,

a support for the bobbin,

a plate carried by the support and having an aperture therein adapted to receive the strand from the bobbin,

a reactionary device mounted on the plate and adapted to engage the strand frictionally around its periphy,

said reactionary device comprising a relatively stationary capstan and a relatively movable capstan, around each of which the strand is wrapped progressively as it moves from the bobbin to the machine, and

means for adjusting the resistance of the member to rotation whereby the tension on the strand may be controlled.

2. A device according to claim 1, wherein a guide bar is positioned adjacent the aperture in the plate and is adapted to frictionally engage the strand and to direct its path of travel from the aperture to the reactionary device.

3. A device according to claim 1, wherein a guide bar is carried by the plate for frictionally engaging the strand and altering its direction of travel between the reactionary device and the machine.

4. A device according to claim 1, wherein the capstans are disposed in axial alignment and wherein the resistance to rotation of the rotatable capstan is attained by varying the frictional engagement of coacting mating faces of the respective capstans.

5. A device according to claim 1, wherein the rotatable capstan has a strand receiving cylindrical groove and wherein the relatively stationary capstan has a strand receiving helical groove.

6. A device according to claim 5, wherein the helical groove on the relatively stationary capstan merges with the annular groove on the relatively rotatable capstan, whereby the strand moves smoothly from one groove to the other.

7. A device according to claim 4, wherein the rotatable capstan is mounted upon an extension of the relatively stationary capstan and is supported by it.

8. A device according to claim 1, wherein the bobbin is mounted for rotation within a canister and a latch is provided for detachably mounting the plate on the canister.

9. A device according to claim 1, wherein the support comprises a rotatable plate, and

a spindle which is attached to the plate and carries the bobbin.

10. A device for maintaining tension on a strand as it is withdrawn from a bobbin by a machine comprising,

a support for said bobbin,

a container-like housing supported at one end on said support adapted to receive said bobbin therein,

a plate mounted on said housing adjacent the end opposite said supported end,

said plate having an aperture therein adapted to receive the strand from said bobbin,

a reactionary device including a rotatable member mounted on said plate and adapted to engage the strand frictionally around its periphery, and

means for adjusting the resistance of the rotatable member to rotation to control the tension on said strand.

11. A device in accordance with claim 10, wherein the axis of rotation of said rotatable member is disposed in generally parallel relation to the lengthwise axis of said bobbin.

5 6 12. A device in accordance with claim 10, wherein 2,491,585 12/ 1949 Sammons 242-130 said container-like housing is open at the end opposite 2,992,792 7/ 1961 van der Hoek 242128 the supported end, and said plate is detach ably mounted in said opening. LEONARD CHRISTIAN, Pflmary Examiner 5 R f :1 d US. Cl. X.R.

e erences 1 e 242 155 UNITED STATES PATENTS 2,048,511 7/1936 Newton 242128 

